Sylvania



(No Model.)

A. W. DAVIDSON&l C. SIGMUND. PIANO.

No. 427,840. Patented May 13, 1.890.

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UNITED STATES PATENT OFFICE.

ARTHUR WV. DAVIDSON AND CHARLES SIGMUND, OF PHILADELPHIA, PENN- I SYLVANIA.

PIANO.

SPECIFICATION forming part of Letters Patent No. 427,840, dated May 13, 1890.

Application filed October 25, 1889. Serial No. 328,146. (No model.)

To all whom it may concern:

Be it known that we, ARTHUR W. DAVID- soN and CHAELEs SIGMUND, both of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented a new and useful Improvement in the Construction of Pianos, of which the following` is a full, clear, and exact description.

Our invention relates to an improvement in 1o the construction of pianos, especially to those of the upright type, and has for its object to provide a means whereby the pin-block will be securely attached to the back timbers or bracings of the instrument, and also to utili 5 ize the attaching mediums as conductors and transmitters of sound.

The invention consists in the combination, With'the pin-block and its support, of tubular or trumpet-shaped bolts and in the novel zo construction and combination of the several parts, as will be hereinafter more fully set forth, and pointed out in the claims.

Reference is to be had to the accompanying drawings, forming a part of this specification,

2 5 in which similar letters and figures of reference indicate corresponding' parts in both the views.

Figure 1 is a partial vertical section through an upright piano, and Fig. 2 is a front elevago tion of the pin-block and a portion of the metal frame connected therewith.

TIn carrying out the invention We do not alter the form of the casing nor the bracings or back timbers or standards 11, and the sound- 3 5 ing-board 12 and the metal frame 13 remain the same, the latter being provided with the usual guide-ribs 14 and stationary pins 15. The Wires or strings 16 are also strung` as heretofore, our improvements relating espe- 4o cially to the novel means for connecting the pin-block 17 to the bracings or back timbers 11.

The means above referred to consist of tubular bolts 19, either straight, conical, or

trumpet-shaped, preferably the latter, which bolts are usually made in two sections a and c', as illustrated in Fig. 1. The section a,

which comprises the body, is of sufficient length to extend through and beyond the pin- 5o block 17 and the bracings or back timbers 11 and is provided with an exterior thread at each extremity. The body-sections are so located that the larger ends will face the front of Jthe casing of the instrument. The section c', which is the bell-section, is interiorly 5 5 threaded at its reduced end and screwed upon the 'front extremity of the body-section to a bearingagainst the front face of the pinblock, as indicated in Fig. 1, and upon the inner or rear end of the body-section c of the 6o tubular bolts a nut 20 is screwed, having a bearing' against the rear face of the bracings or back timbers 1l. Thus as the trumpetsection a acts as a nut, and a nut is placed upon the rear or inner end of the body-scction c, the two parts above named may be so manipulated as toiirmly and effectuallybind the pin-block 17 to the bracings or back tinibers or supports 11. It is also obvious that a bolt or bolts of the description above de- 7o scribed tends to strengthen the pin-block, which, if desirable, is also glued in the ordinary manner to the bracings or back timbers. If in practice it is found desirable, the bellsections c of the bolts 19 may be made to 75 extend a short distance out beyond the front face of the pin-block 17; but preferably the said section is made to extend to the front of the case, as shown.

In addition to the tubular bolts 19, we form 8o at the upper rear portion of the instrument, to the rear of the bracings or back timbers 11, a compartment 21 byproviding a back board at the rear of the instrument. The bolts above described not only serve to effectually prevent the pin-block from being detached from its support by the continual tension upon the wires or strings, but the said bolts also serve as conductors or transmitters of sound, increasing the volume of 9o sound, especially so when the chamber 21 is located at their rear, in which event a series of passages are provided, serving to convey the tone from the back of the instrument to its front.

Having thus described our invention, we claim as new and desire to secure by Letters Patent- 1. The combination, in a piano, with the pin-block, a parallel support to which the roo 3. In a piano or similar instrument, the combination, with the pin-block and its supports, of tubular essentially trumpet-shaped bolts, each comprising a body-section, passing through the said pin-block'and a support therefor, a trumpet-section screwed upon the forward end of the body-section, anda nut screwed upon the rear end of said section, substantially as and for the purpose specied.

ARTHUR W. DAVIDSON. CHARLES SIGMUND. Witnesses:

GEORGE W. CLEMENT, CHARLES H. JOHNSON. 

